t.i.d.DeferredQueue(object) : class documentation

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An event driven queue.

Objects may be added as usual to this queue. When an attempt is made to retrieve an object when the queue is empty, a Deferred is returned which will fire when an object becomes available.

Instance Variables	size	The maximum number of objects to allow into the queue at a time. When an attempt to add a new object would exceed this limit, `QueueOverflow` is raised synchronously. `None` for no limit.
	backlog	The maximum number of `Deferred` gets to allow at one time. When an attempt is made to get an object which would exceed this limit, `QueueUnderflow` is raised synchronously. `None` for no limit.

Method	__init__	Undocumented
Method	put	Add an object to this queue.
Method	get	Attempt to retrieve and remove an object from the queue.
Method	_cancelGet	Remove a deferred d from our waiting list, as the deferred has been canceled.

def __init__(self, size=None, backlog=None): (source)

Undocumented

def _cancelGet(self, d): (source)

Remove a deferred d from our waiting list, as the deferred has been canceled.

Note: We do not need to wrap this in a try/except to catch d not being in self.waiting because this canceller will not be called if d has fired. put() pops a deferred out of self.waiting and calls it, so the canceller will no longer be called.

Parameters d The deferred that has been canceled.

def put(self, obj): (source)

Add an object to this queue.

Raises QueueOverflow Too many objects are in this queue.

def get(self): (source)

Attempt to retrieve and remove an object from the queue.

Returns	a `Deferred` which fires with the next object available in the queue.
Raises	QueueUnderflow	Too many (more than `backlog`) `Deferred`s are already waiting for an object from this queue.

API Documentation for Twisted, generated by pydoctor at 2011-10-27 16:17:34.